Because performance matters so much and there is so much opportunity to get clever with performance, we'll see innovation in getting our code bases to production. Tools like webpack (tree shaking, code splitting) are already doing a lot here, but there is plenty of room to let automated tools work magic on how our code ultimately gets shipped to browsers.

Tom also says:

This is a loss in some ways (who else got their web development start with View Source?) but is a huge win for users, particularly in emerging markets.

It seems to me today's world of GitHub, StackOverflow, and the proliferation of learning resources more than make up for learning via our own website spelunking, not to mention how insightful today's DevTools are, even if what they are looking at isn't hand-authored.